1. Field of the Invention
The invention relates to sprinkler systems, and more particularly, to improvements in sprinklers used in such systems wherein water under pressure causes the sprinkler head and nozzle thereof to pop up to disperse or spray water out of the nozzle.
2. Description of the Prior Art
In my U.S. Pat. No. 3,584,664, I disclosed an improved sprinkler system wherein fluid under pressure flows through a sprinkler and a sprinkler head and nozzle, actuated by the fluid pressure, pops up and sprays water out of the nozzle. Such sprinklers include an impeller actuated by fluid flow and a transmission which converts rotation of the impeller to rotation of the nozzle.
In such sprinklers, suitable means may be provided for varying the pattern of the sprayed fluids. For example, differing types of nozzles may be substituted on the sprinkler. Such means may also take the form of plates or patterns of varying types which can be substituted in the sprinkler for varying the spray of fluid thereout.
It can be appreciated that a wide variety of water flow or volume of water being sprayed out of the nozzle may be obtained in this manner, such as from about 1/2 to 20 gallons of water per minute. During these differing volumes of water spray, it is desired that the nozzle rotate at a predetermined rate. For example, it is preferable that the rate of rotation of the nozzle be neither too slow or too fast. Preferably, a rate of rotation of about one to three minutes for each revolution of the nozzle would be desirable.
However, if the range of water volume spray provided by varying either the nozzle itself or changing the pattern of spray of the nozzle is so great that, in such prior art sprinklers, the nozzle will rotate either too fast or too slow. Accordingly, it is necessary that such sprinklers have means for compensating for differing volumes of water spray out of the nozzles and automatically adjusting the rate of rotation of such nozzles depending on the volume of water spray.